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1.
Eur Radiol ; 32(4): 2384-2392, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34643780

RESUMO

OBJECTIVES: To compare the visibility of intracranial aneurysm wall and thickness quantification between 7 and 3 T vessel wall imaging and evaluate the association between aneurysm size and wall thickness. METHODS: Twenty-nine patients with 29 unruptured intracranial aneurysms were prospectively recruited for 3D T1-weighted vessel wall MRI at both 3 T and 7 T with 0.53 mm (3 T) and 0.4 mm (7 T) isotropic resolution, respectively. Two neuroradiologists independently evaluated wall visibility (0-5 Likert scale), quantified the apparent wall thickness (AWT) using a semi-automated full-width-half-maximum method, calculated wall sharpness, and measured the wall-to-lumen contrast ratio (CRwall/lumen). RESULTS: Twenty-four patients with 24 aneurysms were included in this study. 7 T achieved significantly better aneurysm wall visibility than 3 T (3.6 ± 1.1 vs 2.7 ± 0.8, p = 0.003). AWT measured on 3 T and 7 T had a good correlation (averaged r = 0.63 ± 0.19). However, AWT on 3 T was 15% thicker than that on 7 T (0.52 ± 0.07 mm vs 0.45 ± 0.05 mm, p < 0.001). Wall sharpness on 7 T was 57% higher than that on 3 T (1.95 ± 0.32 mm-1 vs 1.24 ± 0.15 mm-1, p < 0.001). CRwall/lumen on 3 T and 7 T was comparable (p = 0.424). AWT on 7 T was positively correlated with aneurysm size (saccular: r = 0.58, q = 0.046; fusiform: r = 0.67, q = 0.049). CONCLUSIONS: 7 T provides better visualization of intracranial aneurysm wall with higher sharpness than 3 T. 3 T overestimates the wall thickness relative to 7 T. Aneurysm wall thickness is positively correlated with aneurysm size. 7 T MRI is a promising tool to evaluate aneurysm wall in vivo. KEY POINTS: • 7 T provides better visualization of intracranial aneurysm wall with higher sharpness than 3 T. • 3 T overestimates the wall thickness comparing with 7 T. • Aneurysm wall thickness is positively correlated with aneurysm size.


Assuntos
Aneurisma Intracraniano , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos
2.
Small ; 17(43): e2100246, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33818015

RESUMO

The introduction of patterned sapphire substrates (PSS) has been regarded as an effective method to improve the photoelectric performance of 2D layered materials in recent years. Molybdenum disulfide (MoS2 ), an intriguing transition metal 2D materials with splendid photoresponse owing to a direct-indirect bandgap transition at monolayer, shows promising optoelectronics applications. Here, a large-scale, continuous multilayer MoS2 film is prepared on a SiO2 /Si substrate and transferred to flat sapphire substrate and PSS, respectively. An enhanced dynamic distribution of local electric field and concentrated photon excitons across the interface between MoS2 and patterned sapphire substrates are revealed by the finite-difference time-domain simulation. The photoelectric performance of the MoS2 /PSS photodetector is improved under the three lasers of 365, 460, and 660 nm. Under the 365 nm laser, the photocurrent increased by 3 times, noise equivalent power (NEP) decreases to 1.77 × 10-14 W/Hz1/2 and specific detectivity (D*) increases to 1.2 × 1010 Jones. Meanwhile, the responsivity is increased by 7 times at 460 nm, and the response time of the MoS2 /PSS photodetector is also shortened under three wavelengths. The work demonstrates an effective method for enhancing the optical properties of photodetectors and enabling simultaneous detection of broad-spectrum emissions.

3.
Analyst ; 146(12): 4066-4079, 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34048512

RESUMO

Matrix metalloproteinase-1 (MMP-1) is associated with many types of cancers, including oral, colorectal, and brain cancers. This paper describes the fabrication of an MMP-1 immunosensor based on a gold nanoparticle/polyethyleneimine/reduced graphene oxide (AuNP/PEI/rGO)-modified disposable screen-printed electrode (SPE). A microwave-assisted single-step method was employed for the simultaneous reduction of gold and graphene oxide in a PEI environment to avoid AuNP agglomeration. The crystal structure, chemical composition, optical properties, and interior morphology of the materials were probed by X-ray diffraction, Raman spectroscopy, UV-visible spectrometry, and transmission electron microscopy techniques. To assemble a label-free MMP-1 immunosensor layer-by-layer, 3-mercaptopropionic acid was utilized due to its strong sulfur-gold bonding ability, and its tail end was attached to a carboxyl group, allowing the MMP-1 antibody (anti-MMP-1) to be subsequently cross-linked using the traditional N-(3-dimethylaminopropyl) and N' ethylcarbodiimide hydrochloride method. Differential pulse voltammetry analysis showed a linear relationship with MMP-1 concentration in the range of 1-50 ng ml-1 with an R2 value of ∼0.996 (n = 5, RSD < 5%). This immunosensor was successfully applied for MMP-1 detection in urine, saliva, bovine serum, and cell culture media (HSC-3 & C6) of oral and brain cancers showing results comparable to those of the credible ELISA method.


Assuntos
Técnicas Biossensoriais , Grafite , Nanopartículas Metálicas , Nanocompostos , Neoplasias , Animais , Biomarcadores Tumorais , Bovinos , Técnicas Eletroquímicas , Eletrodos , Ouro , Imunoensaio , Limite de Detecção , Metaloproteinase 1 da Matriz , Polietilenoimina
4.
MAGMA ; 34(5): 659-666, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33839985

RESUMO

OBJECTIVES: To determine the intra-individual flow variation in serially acquired studies, and the influence of this variation on subsequent hemodynamic simulations using the inlet flow as a boundary condition. Author: Kindly check and confirm whether the corresponding authors are correctly identified.Confirmed. MATERIALS AND METHODS: This prospective study included 51 patients (37 females and 14 males) with unruptured intracranial aneurysms who have received more than three times follow-up of 2D phase-contrast MR. The flow and velocity parameters were extracted to calculate the reproducibility and variation. Patient-specific computational fluid dynamics simulations were performed using the measured flows. RESULTS: Intraclass correlation coefficients for mean and maximum velocity and flow parameters ranged from 0.77 to 0.90. A 10% CV of mean flow was identified. Variations of 10% in inlet flow resulted in hemodynamic changes including 41.41% of peak systolic wall shear stress; 39.13% of end-diastolic wall shear stress; 2.79% of low shear area at peak systole; 2.12% of low shear area at end diastole: 47.57% of time-averaged wall shear stress; and 0.17% of oscillatory shear index. CONCLUSION: This study identified 10% of intra-individual mean flow variation on phase-contrast MR. Intra-individual flow variation resulted in a non-negligible variation in wall shear stress, but relatively small variation in low shear area in hemodynamic calculations.


Assuntos
Hemodinâmica , Aneurisma Intracraniano , Feminino , Humanos , Hidrodinâmica , Aneurisma Intracraniano/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Modelos Cardiovasculares , Estudos Prospectivos , Reprodutibilidade dos Testes , Estresse Mecânico
5.
Eur Radiol ; 30(1): 301-307, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31218429

RESUMO

PURPOSE: To evaluate and compare wall enhancement patterns in saccular and fusiform intracranial aneurysms using high-resolution black-blood MRI at 7 T. METHODS: Thirty-one patients with 32 unruptured intracranial aneurysms (21 saccular and 11 fusiform) underwent 7-T black-blood MRI. Aneurysm wall enhancement (AWE) was categorized as follows: no wall enhancement (NWE), focal wall enhancement (FWE), and uniform wall enhancement (UWE). The degree of enhancement was scored as follows: 0 (no enhancement), 1 (signal intensity (SI) of the aneurysm wall less than that of the pituitary infundibulum), and 2 (equal to that of the pituitary infundibulum). The chi-squared test was used to compare the AWE pattern and degree between saccular and fusiform aneurysms. RESULTS: In saccular aneurysms, 12/21 (57%) enhanced. Of these, 9 showed FWE (5 grade 1 and 4 grade 2), and 3 showed UWE (2 grade 1 and 1 grade 2). In fusiform aneurysms, 11/11 (100%) enhanced. Of these, 1 showed FWE and 10 showed UWE. All fusiform aneurysms had grade-2 enhancement. Fusiform aneurysms had more extensive and higher SI AWE than saccular aneurysms (p < 0.01) despite having a similar size (6.9 ± 3.0 mm vs. 8.0 ± 2.9, p = 0.23). For saccular aneurysm, larger aneurysm size was correlated with higher degree of enhancement with Pearson's r = 0.64 (p = 0.002). CONCLUSION: Intracranial fusiform aneurysms had enhancement of higher SI and that covered a more extensive area than saccular aneurysms, which might indicate differences in vessel wall pathology. KEY POINTS: • Intracranial aneurysm wall enhancement can be reliably characterized by 7-T black-blood MRI. • AWE in intracranial fusiform aneurysms presents over a larger surface area and with greater signal intensity as compared with that in saccular aneurysms, which might indicate differences in pathology. • Stronger signal intensity of AWE correlates with the aneurysm size in saccular aneurysms.


Assuntos
Aneurisma Intracraniano/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Aneurisma Intracraniano/patologia , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Adulto Jovem
6.
MAGMA ; 33(6): 855-863, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32297164

RESUMO

OBJECTIVES: This study aims to evaluate the reproducibility of measures of plaque morphology in serially acquired black-blood MRI of untreated atherosclerotic femoral arteries. MATERIALS AND METHODS: MR studies was obtained from 42 timepoints, on 12 patients with known femoral artery atherosclerosis. Images with a 3D isotropic FLASH with DANTE-prepared black blood contrast (DASH) at a 3-T scanner were acquired at baseline, within 1 week, and at 1 month. Six of the patients were scanned additionally at 6 months. Inter-scan and inter-observer variations of arterial area/volume measurements were evaluated. RESULTS: Measurement of vessel area, lumen area, wall area and wall volume showed inter-scan intraclass correlation coefficients (ICC) ranging from 0.92 to 0.97 for 3 scans, 0.91-0.97 for 4 scans, and inter-observer ICCs of 0.89-0.96. Among 3 scans, the coefficients of variance (CV) for the vessel area, lumen area, wall area and wall volume were 4.1%, 6.5%, 7.5%, and 4.4%. CVs among 4 scans ranged from 4.4% to 7.9%, and interobserver CVs ranged from 6.1% to 11.8% for the different area/volume measurements. CONCLUSION: DASH MRI is useful for quantifying atherosclerotic vessel area and volume of femoral arteries with low variability among serial repeated scans and between observers.


Assuntos
Aterosclerose , Placa Aterosclerótica , Aterosclerose/diagnóstico por imagem , Artérias Carótidas , Artéria Femoral/diagnóstico por imagem , Humanos , Imageamento Tridimensional , Variações Dependentes do Observador , Placa Aterosclerótica/diagnóstico por imagem , Reprodutibilidade dos Testes
7.
J Magn Reson Imaging ; 50(3): 994-1001, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30694008

RESUMO

BACKGROUND: Intraluminal thrombus (ILT) signal intensity on MRI has been studied as a potential marker of abdominal aortic aneurysm (AAA) progression. PURPOSE: 1) To characterize the relationship between ILT signal intensity and AAA diameter; 2) to evaluate ILT change over time; and 3) to assess the relationship between ILT features and AAA growth. STUDY TYPE: Prospective. SUBJECTS: Eighty AAA patients were imaged, and a subset (n = 41) were followed with repeated MRI for 16 ± 9 months. FIELD STRENGTH/SEQUENCE: 3D black-blood fast-spin-echo sequence at 3 T. ASSESSMENT: ILT was designated as "bright" if the signal was greater than 1.2 times that of adjacent psoas muscle. AAAs were divided into three groups based on ILT: Type 1: bright ILT; Type 2: isointense ILT; Type 3: no ILT. During follow-up, an active ILT change was defined as new ILT formation or an increase in ILT signal intensity to bright; stable ILT was defined as no change in ILT type or ILT became isointense from bright previously. STATISTICAL TESTS: Shapiro-Wilk test; Mann-Whitney U-test; Fisher's exact test; Kruskal-Wallis test; Spearman's r; intraclass correlation coefficient (ICC), Cohen's kappa. RESULTS: AAAs with Type 1 ILT were larger than those with Types 2 and 3 ILT (5.1 ± 1.1 cm, 4.4 ± 0.9 cm, 4.2 ± 0.8 cm, P = 0.008). The growth rate of AAAs with Type 1 ILT was significantly greater than that of AAAs with Types 2 and 3 ILT (2.6 ± 2.5, 0.6 ± 1.3, 1.5 ± 0.6 mm/year, P = 0.01). During follow-up, AAAs with active ILT changes had a 3-fold increased growth rate compared with AAAs with stable ILT (3.6 ± 3.0 mm/year vs. 1.2 ± 1.5 mm/year, P = 0.008). DATA CONCLUSION: AAAs with bright ILT are larger in diameter and grow faster. Active ILT change is associated with faster AAA growth. Black-blood MRI can characterize ILT features and monitor their change over time, which may provide new insights into AAA risk assessment. LEVEL OF EVIDENCE: 2 Technical Efficacy Stage: 5 J. Magn. Reson. Imaging 2019;50:994-1001.


Assuntos
Aneurisma da Aorta Abdominal/complicações , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Trombose/complicações , Trombose/diagnóstico por imagem , Idoso , Aorta Abdominal/diagnóstico por imagem , Aorta Abdominal/patologia , Aneurisma da Aorta Abdominal/patologia , Estudos Transversais , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Estudos Prospectivos
8.
Biomed Microdevices ; 20(2): 34, 2018 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-29627886

RESUMO

Remote-controlled vascular interventional robots (RVIRs) are being developed to increase the accuracy of surgical operations and reduce the number of occupational risks sustained by intervening physicians, such as radiation exposure and chronic neck/back pain. However, complex control of the RVIRs improves the doctor's operation difficulty and reduces the operation efficiency. Furthermore, incomplete sterilization of the RVIRs will increase the risk of infection, or even cause medical accidents. In this study, we introduced a novel method that provides higher operation efficiency than a previous prototype and allows for complete robot sterilization. A prototype was fabricated and validated through laboratory setting experiments and an in-human experiment. The results illustrated that the proposed RVIR has better performance compared with the previous prototype, and preliminarily demonstrated that the proposed RVIR has good safety and reliability and can be used in clinical surgeries.


Assuntos
Procedimentos Cirúrgicos Robóticos/instrumentação , Procedimentos Cirúrgicos Vasculares/instrumentação , Desenho de Equipamento , Humanos , Fatores de Tempo
9.
Opt Express ; 25(8): A253-A263, 2017 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-28437893

RESUMO

As it already made huge effect in the commercialization of silicon and other photovoltaics, interface engineering is dispensable in the current and future evolution of hybrid perovskite solar cells (PSCs) techniques. In order to solve carriers' recombination and detention at the cathode side of planar PSCs, in this work, Ruthenium acetylacetonate (RuAcac) was successfully adopted as a reliable and stable cathode interfacial layer (CIL) to improve the inverted planar PSCs. The power conversion efficiency of the optimal devices was enhanced from 12.74% for the control device without RuAcac, to 17.15% for the RuAcac based devices, with an open circuit voltage of 1.077 V, a short circuit current density of 21.28 mA/cm2, and fill factor of 74.7% correspondingly. A series of photon-physics and microscopy protocols, including EQE, UPS, XPS, PL and SKPM, were used to discover the function of RuAcac CIL. Those results confirms an identical conclusion that RuAcac enables the formation of quasi-ohmic contact at the cathode side by eliminating the energy level barrier between the LUMO of PCBM and Fermi level of silver electrode. The low temperature and facile processed Ruthenium acetylacetonate in this work definitely offer us a robust interface-engineering way for the perovskite solar cells and also their commercialization.

10.
Int J Nanomedicine ; 19: 10537-10550, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39435043

RESUMO

Background: Phototherapy based on photocatalytic semiconductor nanomaterials has received considerable attention for the cancer treatment. Nonetheless, intense efficacy for in vivo treatment is restricted by inadequate photocatalytic activity and visible light response. Methods: In this study, we designed a photocatalytic heterostructure using graphitic carbon nitride (g-C3N4) and tin disulfide (SnS2) to synthesize g-C3N4/SnS2 heterostructure through hydrothermal process. Furthermore, Au nanoparticles were decorated in situ deposition on the surface of the g-C3N4/SnS2 heterostructure to form g-C3N4/SnS2@Au nanoparticles. Results: The g-C3N4/SnS2@Au nanoparticles generated intense reactive oxygen species radicals under near-infrared (NIR) laser irradiation through photodynamic therapy (PDT) pathways (Type-I and Type-II). These nanoparticles exhibited enhanced photothermal therapy (PTT) efficacy with high photothermal conversion efficiency (41%) when subjected to 808 nm laser light, owing to the presence of Au nanoparticles. The in vitro studies have indicated that these nanoparticles can induce human liver carcinoma cancer cell (HepG2) apoptosis (approximately 80% cell death) through the synergistic therapeutic effects of PDT and PTT. The in vivo results demonstrated that these nanoparticles exhibited enhanced efficient antitumor effects based on the combined effects of PDT and PTT. Conclusion: The g-C3N4/SnS2@Au nanoparticles possessed enhanced photothermal properties and PDT effect, good biocompatibility and intense antitumor efficacy. Therefore, these nanoparticles could be considered promising candidates through synergistic PDT/PTT effects upon irradiation with NIR laser for cancer treatment.


Assuntos
Ouro , Grafite , Raios Infravermelhos , Nanopartículas Metálicas , Fotoquimioterapia , Terapia Fototérmica , Ouro/química , Humanos , Fotoquimioterapia/métodos , Terapia Fototérmica/métodos , Animais , Nanopartículas Metálicas/química , Células Hep G2 , Camundongos , Grafite/química , Compostos de Nitrogênio/química , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Neoplasias Hepáticas/terapia , Camundongos Endogâmicos BALB C , Sulfetos/química , Sulfetos/farmacologia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Camundongos Nus
11.
Talanta ; 282: 127008, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39406096

RESUMO

Listeria monocytogenes is a gram-positive bacterium that causes listeriosis in humans. This contaminates the ready-to-eat food products and compromises their safety. Thus, detecting its presence in food samples with high sensitivity and reliability is necessary. Herein, we propose a label-free electrochemical immunosensor based on a mussel-inspired polydopamine-modified zinc molybdate/MXene (PDA@ZnMoO4/MXene) composite for effective and rapid detection of L. monocytogenes in food products. Spectrophotometry approaches were employed to examine the resulting composites. Voltammetry and impedimetry techniques were used to confirm the step-by-step assembly of the immunosensor and its sensitive detection of L. monocytogenes in various food products, such as milk and smoked seafood. The results demonstrated the practicality of the constructed immunosensor, with an appreciable linearity of 10-107 CFU/ml and a reasonably low detection limit (LOD, 12 CFU/ml). Moreover, the immunosensor exhibited excellent selectivity for microbial cocktails and acceptable repeatability, reproducibility, and storage stability. Thus, we believe that the proposed sensitive, reliable, and label-free immunosensor based on the PDA surface modification technique for detecting L. monocytogenes can be extended to monitor various food-borne pathogens to ensure food safety.

12.
ACS Appl Mater Interfaces ; 16(32): 42588-42596, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39083669

RESUMO

Stacking of van der Waals (vdW) heterostructures and chemical element doping have emerged as crucial methods for enhancing the performance of semiconductors. This study proposes a novel strategy for modifying heterostructures by codoping MoS2 with two elements, Re and W, resulting in the construction of a RexWyMo1-x-yS2/WSe2 heterostructure for the preparation of photodetectors. This approach incorporates multiple strategies to enhance the performance, including hybrid stacking of materials, type-II band alignment, and regulation of element doping. As a result, the RexWyMo1-x-yS2/WSe2 devices demonstrate exceptional performance, including high photoresponsivity (1550.22 A/W), high detectivity (8.17 × 1013 Jones), and fast response speed (rise/fall time, 190 ms/1.42 s). Moreover, the ability to tune the band gap through element doping enables spectral response in the ultraviolet (UV), visible light, and near-infrared (NIR) regions. This heterostructure fabrication scheme highlights the high sensitivity and potential applications of vdW heterostructure (vdWH) in optoelectronic devices.

13.
Biomater Adv ; 158: 213778, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38325029

RESUMO

Combining chemodynamic therapy (CDT) with photothermal therapy (PTT) has developed as a promising approach for cancer treatment, as it enhances therapeutic efficiency through redox reactions and external laser induction. In this study, we designed metal organic framework (MOF) -derived Cu5Zn8/HPCNC through a carbonization process and decorated them with gold nanoparticles (Au@Cu5Zn8/HPCNC). The resulting nanoparticles were employed as a photothermal agent and Fenton catalyst. The Fenton reaction facilitated the conversation of Cu2+ to Cu+ through reaction with local H2O2, generating reactive hydroxyl radicals (·OH) with potent cytotoxic effects. To enhance the Fenton-like reaction and achieve combined therapy, laser irradiation of the Au@Cu5Zn8/HPCNC induced efficient photothermal therapy by generating localized heat. With a significantly increased absorption of Au@Cu5Zn8/HPCNC at 808 nm, the photothermal efficiency was determined to be 57.45 %. Additionally, Au@Cu5Zn8/HPCNC demonstrated potential as a contrast agent for magnetic resonance imaging (MRI) of cancers. Furthermore, the synergistic combination of PTT and CDT significantly inhibited tumor growth. This integrated approach of PTT and CDT holds great promise for cancer therapy, offering enhanced CDT and modulation of the tumor microenvironment (TME), and opening new avenues in the fight against cancer.


Assuntos
Nanopartículas Metálicas , Estruturas Metalorgânicas , Ouro , Nanopartículas Metálicas/uso terapêutico , Terapia Fototérmica , Porosidade , Microambiente Tumoral , Carbono , Imageamento por Ressonância Magnética , Zinco
14.
ACS Appl Mater Interfaces ; 16(10): 12805-12812, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38422468

RESUMO

Polarization-sensitive photodetectors based on two-dimensional anisotropic materials still encounter the issues of narrow spectral coverage and low polarization sensitivity. To address these obstacles, anisotropic As0.6P0.4 with a narrow band gap has been integrated with WSe2 to construct a type-II heterostructure, realizing a high-performance polarization-sensitive photodetector with broad spectral range from 405 to 2200 nm. By operating in photovoltaic mode at zero bias, the device shows a very low dark current of ∼0.02 picoampere, high responsivity of 492 m A/W, and high photoswitching ratio of 6 × 104, yielding a high specific detectivity of 1.4 × 1012 Jones. The strong in-plane anisotropy of As0.6P0.4 endows the device with a capability of polarization-sensitive detection with a high polarization ratio of 6.85 under a bias voltage. As an image sensor and signal receiver, the device shows great potential in imaging and optical communication applications. This work develops an anisotropic vdW heterojunction to realize polarization-sensitive photodetectors with wide spectral coverage, fast response, and high sensitivity, providing a new candidate for potential applications of polarization-resolved electronics and photonics.

15.
Colloids Surf B Biointerfaces ; 234: 113755, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38241894

RESUMO

In terms of cancer-related deaths among women, breast cancer (BC) is the most common. Clinically, human epidermal growth receptor 2 (HER2) is one of the most commonly used diagnostic biomarkers for facilitating BC cell proliferation and malignant growth. In this study, a disposable gold electrode (DGE) modified with gold nanoparticle-decorated Ti3C2Tx (Au/MXene) was utilized as a sensing platform to immobilize the capturing antibody (Ab1/Au/MXene). Subsequently, nitrogen-doped graphene (NG) with a metal-organic framework (MOF)-derived copper-manganese-cobalt oxide, tagged as NG/CuMnCoOx, was used as a probe to label the detection antibody (Ab2). A sandwich-type immunosensor (NG/CuMnCoOx/Ab2/HER2-ECD /Ab1/Au/MXene/DGE) was developed to quantify HER2-ECD. NG/CuMnCoOx enhances the conductivity, electrocatalytic active sites, and surface area to immobilize Ab2. In addition, Au/MXene facilitates electron transport and captures more Ab1 on its surface. Under optimal conditions, the resultant immunosensor displayed an excellent linear range of 0.0001 to 50.0 ng. mL-1. The detection limit was 0.757 pg·mL-1 with excellent selectivity, appreciable reproducibility, and high stability. Moreover, the applicability for determining HER2-ECD in human serum samples indicates its ability to monitor tumor markers clinically.


Assuntos
Técnicas Biossensoriais , Neoplasias da Mama , Grafite , Compostos de Manganês , Nanopartículas Metálicas , Estruturas Metalorgânicas , Nitritos , Óxidos , Elementos de Transição , Humanos , Feminino , Biomarcadores Tumorais , Grafite/química , Estruturas Metalorgânicas/química , Ouro/química , Reprodutibilidade dos Testes , Nanopartículas Metálicas/química , Neoplasias da Mama/diagnóstico , Imunoensaio , Técnicas Eletroquímicas , Limite de Detecção , Anticorpos Imobilizados/química
16.
Front Neurol ; 15: 1339144, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39233674

RESUMO

Background and objective: The rupture risk of intracranial aneurysms (IAs) is related to their arterial origin, but whether the different segments of the artery have different risks and act as independent risk factors is still unknown. Our study aimed to investigate the rupture risk of IAs in different arterial segments in a large Chinese cohort. Methods: Imaging and clinical data of consecutive patients with IAs diagnosed by Computed Tomography angiography (CTA) from January 2013 to December 2022 were collected. Two neuroradiologists independently identified ruptured and unruptured IAs based on imaging and medical records. The internal carotid artery (ICA), middle cerebral artery (MCA), anterior cerebral artery (ACA), vertebral artery (VA), and posterior cerebral artery (PCA) were segmented according to the Bouthillier and Fischer segmentation methods. Stenoses of the proximal parent vessel were evaluated and documented. The Institutional Review Board (IRB) at Beijing Tiantan Hospital approved this retrospective study. Results: A total of 3,837 aneurysms {median size 3.5 mm [interquartile range (IQR) 2.6-5.1 mm]; 532 ruptured} were included in this study from 2,968 patients [mean age: 57 years (IQR 50-64); male patients: 1,153]. Ruptured aneurysms were most commonly located in the posterior inferior cerebellar artery (PICA) (52.9%), anterior communicating artery (ACoA) (33.8%), other locations (33.3%), ACA (22.4%), and basilar artery (BA) (21.4%). The locations with the highest likelihood of rupture were the C7 ICA (21.3%), M2 MCA (24.0%), distal MCA (25.0%), and A2 ACA (28.1%). IAs originating from the C7 (p < 0.001), dM1 (p = 0.022), and dA1 (p = 0.021) segments were independent risk factors for rupture. IAs without stenosis of the proximal parent vessel were associated with a higher risk of rupture (p = 0.023). Conclusion: There are unique associations between the origins of aneurysms from various arterial segments. Aneurysms originating from the anterior communicating artery (ACoA), BA, PICA, A2, dA, C7, and M2 indicate a higher risk of rupture. Aneurysms originating from C4, C5, and C6 indicate a lower risk of rupture. C7 IAs, ACoA IAs, and PICA IAs seem to be independent risk factors.

17.
J Mater Chem B ; 12(15): 3569-3593, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38494982

RESUMO

In recent years, inorganic nanoparticles (NPs) have attracted increasing attention as potential theranostic agents in the field of oncology. Photothermal therapy (PTT) is a minimally invasive technique that uses nanoparticles to produce heat from light to kill cancer cells. PTT requires two essential elements: a photothermal agent (PTA) and near-infrared (NIR) radiation. The role of PTAs is to absorb NIR, which subsequently triggers hyperthermia within cancer cells. By raising the temperature in the tumor microenvironment (TME), PTT causes damage to the cancer cells. Nanoparticles (NPs) are instrumental in PTT given that they facilitate the passive and active targeting of the PTA to the TME, making them crucial for the effectiveness of the treatment. In addition, specific targeting can be achieved through their enhanced permeation and retention effect. Thus, owing to their significant advantages, such as altering the morphology and surface characteristics of nanocarriers comprised of PTA, NPs have been exploited to facilitate tumor regression significantly. This review highlights the properties of PTAs, the mechanism of PTT, and the results obtained from the improved curative efficacy of PTT by utilizing NPs platforms.


Assuntos
Hipertermia Induzida , Nanopartículas , Neoplasias , Humanos , Fototerapia/métodos , Hipertermia Induzida/métodos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Nanomedicina Teranóstica/métodos , Microambiente Tumoral
18.
Food Chem ; 455: 139920, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38850994

RESUMO

This work presents a hydrothermal method followed by a sonochemical treatment for synthesizing tantalum decorated on iron selenide (Ta/FeSe2) integrated with nitrogen-doped graphene (NGR) as a susceptible electrode material for detecting trolox (TRX) in berries samples. The surface morphology, structural characterizations, and electrochemical performances of the synthesized Ta/FeSe2/NGR composite were analyzed via spectrophotometric and voltammetry techniques. The GCE modified with Ta/FeSe2/NGR demonstrated an impressive linear range of 0.1 to 580.3 µM for TRX detection. Additionally, it achieved a remarkable limit of detection (LOD) of 0.059 µM, and it shows a high sensitivity of 2.266 µA µÐœ-1 cm-2. Here, we used density functional theory (DFT) to investigate the structures of TRX and TRX quinone and the locations of energy levels and electron transfer sites. The developed sensor exhibits significant selectivity, satisfactory cyclic and storage stability, and notable reproducibility. Moreover, the practicality of TRX was assessed in different types of berries, yielding satisfactory recoveries.


Assuntos
Cromanos , Frutas , Grafite , Nitrogênio , Tantálio , Grafite/química , Frutas/química , Nitrogênio/química , Tantálio/química , Cromanos/química , Cromanos/análise , Teoria da Densidade Funcional , Técnicas Eletroquímicas , Limite de Detecção , Eletrodos , Ferro/química , Ferro/análise
19.
Heliyon ; 10(9): e30006, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38694075

RESUMO

Background: Wall shear stress (WSS) has been proved to be related to the formation, development and rupture of intracranial aneurysms. Aneurysm wall enhancement (AWE) on magnetic resonance imaging (MRI) can be caused by inflammation and have confirmed its relationship with low WSS. High WSS can also result in inflammation but the research of its correlation with AWE is lack because of the focus on large aneurysms limited by 3T MRI in most previous studies.This study aimed to assess the potential association between high or low WSS and AWE in different aneuryms. Especially the relationship between high WSS and AWE in small aneurysm. Methods: Forty-three unruptured intracranial aneurysms in 42 patients were prospectively included for analysis. 7.0 T MRI was used for imaging. Aneurysm size was measured on three-dimensional time-of-flight (TOF) images. Aneurysm-to-pituitary stalk contrast ratio (CRstalk) was calculated on post-contrast black-blood T1-weighted fast spin echo sequence images. Hemodynamics were assessed by four-dimensional flow MRI. Results: The small aneurysms group had more positive WSS-CRstalk correlation coefficient distribution (dome: 78.6 %, p = 0.009; body: 50.0 %, p = 0.025), and large group had more negative coefficient distribution (dome: 44.8 %, p = 0.001; body: 69.0 %, p = 0.002). Aneurysm size was positively correlated with the significant OSI-CRstalk correlation coefficient at the dome (p = 0.012) and body (p = 0.010) but negatively correlated with the significant WSS-CRstalk correlation coefficient at the dome (p < 0.001) and body (p = 0.017). Conclusion: AWE can be mediated by both high and low WSS, and translate from high WSS- to low WSS-mediated pathways as size increase. Additionally, AWE may serve as an indicator of the stage of aneurysm development via different correlations with hemodynamic factors.

20.
ACS Appl Mater Interfaces ; 16(20): 25622-25636, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38739745

RESUMO

Breast cancer is a malignant tumor with a high mortality rate among women. Therefore, it is necessary to develop novel therapies to effectively treat this disease. In this study, iron selenide nanorods (FeSe2 NRs) were designed for use in magnetic hyperthermic, photothermal, and chemodynamic therapy (MHT/PTT/CDT) for breast cancer. To illustrate their efficacy, FeSe2 NRs were modified with the chemotherapeutic agent methotrexate (MTX). MTX-modified FeSe2 (FeSe2-MTX) exhibited excellent controlled drug release properties. Fe2+ released from FeSe2 NRs induced the release of •OH from H2O2 via a Fenton/Fenton-like reaction, enhancing the efficacy of CDT. Under alternating magnetic field (AMF) stimulation and 808 nm laser irradiation, FeSe2-MTX exerted potent hyperthermic and photothermal effects by suppressing tumor growth in a breast cancer nude mouse model. In addition, FeSe2 NRs can be used for magnetic resonance imaging in vivo by incorporating their superparamagnetic characteristics into a single nanomaterial. Overall, we presented a novel technique for the precise delivery of functional nanosystems to tumors that can enhance the efficacy of breast cancer treatment.


Assuntos
Neoplasias da Mama , Hipertermia Induzida , Metotrexato , Camundongos Nus , Nanotubos , Metotrexato/química , Metotrexato/farmacologia , Animais , Nanotubos/química , Camundongos , Feminino , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Camundongos Endogâmicos BALB C , Terapia Fototérmica , Ferro/química , Compostos de Selênio/química , Compostos de Selênio/farmacologia , Compostos de Selênio/efeitos da radiação , Linhagem Celular Tumoral , Raios Infravermelhos
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